Re: [PATCH bpf-next] bpf: devmap: move drop error path to devmap for XDP_REDIRECT
From: Edward Cree <ecree.xilinx@gmail.com>
Date: 2021-02-17 20:16:26
Also in:
bpf
On 17/02/2021 13:56, Lorenzo Bianconi wrote:
quoted hunk ↗ jump to hunk
We want to change the current ndo_xdp_xmit drop semantics because it will allow us to implement better queue overflow handling. This is working towards the larger goal of a XDP TX queue-hook. Move XDP_REDIRECT error path handling from each XDP ethernet driver to devmap code. According to the new APIs, the driver running the ndo_xdp_xmit pointer, will break tx loop whenever the hw reports a tx error and it will just return to devmap caller the number of successfully transmitted frames. It will be devmap responsability to free dropped frames. Move each XDP ndo_xdp_xmit capable driver to the new API<snip>> diff --git a/drivers/net/ethernet/sfc/tx.c b/drivers/net/ethernet/sfc/tx.c index 1665529a7271..0c6650d2e239 100644--- a/drivers/net/ethernet/sfc/tx.c +++ b/drivers/net/ethernet/sfc/tx.c@@ -412,14 +412,6 @@ netdev_tx_t __efx_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb return NETDEV_TX_OK; } -static void efx_xdp_return_frames(int n, struct xdp_frame **xdpfs) -{ - int i; - - for (i = 0; i < n; i++) - xdp_return_frame_rx_napi(xdpfs[i]); -} - /* Transmit a packet from an XDP buffer * * Returns number of packets sent on success, error code otherwise.@@ -492,12 +484,7 @@ int efx_xdp_tx_buffers(struct efx_nic *efx, int n, struct xdp_frame **xdpfs, if (flush && i > 0) efx_nic_push_buffers(tx_queue); - if (i == 0) - return -EIO; - - efx_xdp_return_frames(n - i, xdpfs + i); - - return i; + return i == 0 ? -EIO : i; }
Could this be "return i ?: -EIO;"? (I'm undecided on whether that would actually be better.) Either way, have an Acked-by: Edward Cree <ecree.xilinx@gmail.com> for the sfc part.